Wemos D1 ESP8266 based board

The wemos d1 is an Arduino Uno-like wifi board based on ESP-8266EX. You can use the Arduino IDE, NodeMCU and there are other development environments available

Wemos D1 ESP8266 based board

There is a USB connector, note that its a micro type and you can use this and also OTA for programming. I used the USB cable, it was the easiest way. The board can be pwered via the usb cable or you can plug in an external DC source, in the range of 7v to 24v. I recommend 9v.

The table below shows the pins of the wemos d1, the main difference between this and the Arduino UNO is that there is only one Analog input. All I/O pins are 3.3v, so some arduino shields will not work and obviously be careful what you connect to these pins.

Pin

Function

ESP-8266 Pin

D0

RX

GPIO3

D1

TX

GPIO1

D2

IO

GPIO16

D3(D15)

IO,SCL

GPIO5

D4(D14)

IO,SDA

GPIO4

D5(D13)

IO,SCK

GPIO14

D6(D12)

IO,MISO

GPIO12

D7(D11)

IO,MOSI

GPIO13

D8

IO,Pull-up

GPIO0

D9

IO,pull-up, BUILTIN_LED

GPIO2

D10

IO,pull-down,SS

GPIO15

A0

Analog Input

A0

Installing with Boards Manager

Starting with Arduino IDE 1.6.4, the software allows installation of third-party platform packages using Boards Manager. There are packages available for Windows, Mac OS, and Linux (32 and 64 bit).

void setup(){
pinMode(BUILTIN_LED, OUTPUT);// Initialize the BUILTIN_LED pin as an output}// the loop function runs over and over again forevervoid loop(){
digitalWrite(BUILTIN_LED, LOW);// Turn the LED on (Note that LOW is the voltage level// but actually the LED is on; this is because// it is acive low on the ESP-01)
delay(1000);// Wait for a second
digitalWrite(BUILTIN_LED, HIGH);// Turn the LED off by making the voltage HIGH
delay(2000);// Wait for two seconds (to demonstrate the active low LED)}